Towards Repairing Scenario-Based Models with Rich Events

Repairing legacy systems is a difficult and error-prone task: often, limited knowledge of the intricacies of these systems could make an attempted repair result in new errors. Consequently, it is desirable to repair such systems in an automated and sound way. Here, we discuss our ongoing work on the automated repair of Scenario-Based Models: fully executable models that describe a system using scenario objects that model its individual behaviors. We show how rich, scenario-based models can be model-checked, and then repaired to prevent various safety violations. The actual repair is performed by adding new scenario objects to the model, and without altering existing ones—in a way that is well aligned with the principles of scenario-based modeling. In order to automate our repair approach, we leverage off-the-shelf SMT solvers. We describe the main principles of our approach, and discuss our plans for future work.